Segment Information - Schedule of Segment Reporting (Details) - USD ($) $ in Millions		3 Months Ended												12 Months Ended
		Sep. 30, 2016		Jun. 30, 2016	[1]	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015		Jun. 30, 2015	[2]	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2016		Sep. 30, 2015		Sep. 30, 2014
Segment Reporting Information
Revenues		$ 976.2	[1]	$ 1,130.8		$ 1,972.1	$ 1,606.6	$ 1,082.8		$ 1,148.1		$ 2,455.6	$ 2,004.6	$ 5,685.7		$ 6,691.1	[3]	$ 8,277.3	[3]
Cost of sales														2,437.5		3,736.5	[3]	5,175.7	[3]
Operating income (loss)		(88.6)	[1]	155.7		615.4	305.5	(6.6)		56.1		702.1	83.3	988.0		834.9	[3]	1,005.6	[3]
Loss from equity investees		(0.1)	[1]	0.0		0.0	(0.1)	(0.1)		0.0		(0.1)	(1.0)	(0.2)		(1.2)	[3]	(0.1)	[3]
Loss on extinguishments of debt		(11.8)	[1]	(37.1)		0.0	0.0	0.0		0.0		0.0	0.0	(48.9)		0.0		0.0
Interest expense														(228.9)		(241.9)	[3]	(237.7)	[3]
Income (loss) before income taxes														710.0		591.8	[3]	767.8	[3]
Net income (loss) attributable to UGI		(43.8)	[1]	$ 60.7		$ 233.2	$ 114.6	(9.2)		$ 9.6		$ 246.5	$ 34.1	364.7		281.0	[3]	337.2	[3]
Depreciation and amortization														400.9		374.1	[3]	362.9	[3]
Noncontrolling interests’ net income (loss)														124.1		133.0	[3]	195.4	[3]
Total assets		10,847.2						10,514.2	[3]					10,847.2		10,514.2	[3]	10,062.6	[3]
Short-term borrowings		291.7						189.9	[3]					291.7		189.9	[3]	210.8	[3]
Capital expenditures														604.6		475.4	[3]	436.4	[3]
Investments in equity investees		25.9						16.2	[3]					25.9		16.2	[3]	0.6	[3]
Goodwill		2,989.0						2,953.4	[3]					2,989.0		2,953.4	[3]	2,833.4	[3]
Pretax gains (losses) on unsettled commodity derivative instruments														91.6		(119.1)		(18.0)
AmeriGas Propane
Segment Reporting Information
Loss on extinguishments of debt														(48.9)		0.0		0.0
Interest expense														(164.1)		(162.8)		(165.6)
Income (loss) before income taxes														143.3		264.8		306.4
Depreciation and amortization														190.0		194.9		197.2
Partnership Adjusted EBITDA														543.0		619.2		664.8
UGI France | Term Loan
Segment Reporting Information
Pretax loss on early extinguishment of debt																10.3
Eliminations
Segment Reporting Information
Revenues	[4]													(143.9)		(231.4)	[3]	(321.3)	[3]
Cost of sales	[4]													(141.5)		(227.6)	[3]	(317.7)	[3]
Operating income (loss)														0.2		(0.9)	[3]	0.2	[3]
Loss from equity investees														0.0		0.0	[3]	0.0	[3]
Loss on extinguishments of debt														0.0
Interest expense														0.0		0.0	[3]	0.0	[3]
Income (loss) before income taxes														0.2		(0.9)	[3]	0.2	[3]
Net income (loss) attributable to UGI														0.1		(0.6)	[3]	0.0	[3]
Depreciation and amortization														(0.2)		0.0	[3]	0.0	[3]
Noncontrolling interests’ net income (loss)														0.0		0.0	[3]	0.0	[3]
Total assets		(136.6)						(90.4)	[3]					(136.6)		(90.4)	[3]	(86.5)	[3]
Short-term borrowings		0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Capital expenditures														0.0		0.0	[3]	0.0	[3]
Investments in equity investees		0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Goodwill		0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Operating Segments | AmeriGas Propane
Segment Reporting Information
Revenues														2,311.8		2,885.3	[3]	3,712.9	[3]
Cost of sales														864.8		1,340.0	[3]	2,107.1	[3]
Operating income (loss)														356.3		427.6	[3]	472.0	[3]
Loss from equity investees														0.0		0.0	[3]	0.0	[3]
Loss on extinguishments of debt														(48.9)
Interest expense														(164.1)		(162.8)	[3]	(165.6)	[3]
Income (loss) before income taxes														143.3		264.8	[3]	306.4	[3]
Net income (loss) attributable to UGI														43.2		61.0	[3]	63.0	[3]
Depreciation and amortization														190.0		194.9	[3]	197.2	[3]
Noncontrolling interests’ net income (loss)														75.9		167.9	[3]	195.8	[3]
Partnership Adjusted EBITDA	[5]													543.0		619.2	[3]	664.8	[3]
Total assets		4,071.8						4,128.4	[3]					4,071.8		4,128.4	[3]	4,351.4	[3]
Short-term borrowings		153.2						68.1	[3]					153.2		68.1	[3]	109.0	[3]
Capital expenditures														101.7		102.0	[3]	113.9	[3]
Investments in equity investees		0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Goodwill		1,978.3						1,956.0	[3]					1,978.3		1,956.0	[3]	1,945.1	[3]
Operating Segments | UGI Utilities
Segment Reporting Information
Revenues														768.5		1,041.6	[3]	1,086.9	[3]
Cost of sales														289.8		510.8	[3]	562.9	[3]
Operating income (loss)														200.9		241.7	[3]	246.4	[3]
Loss from equity investees														0.0		0.0	[3]	0.0	[3]
Loss on extinguishments of debt														0.0
Interest expense														(37.6)		(41.1)	[3]	(38.5)	[3]
Income (loss) before income taxes														163.3		200.6	[3]	207.9	[3]
Net income (loss) attributable to UGI														97.4		121.1	[3]	124.1	[3]
Depreciation and amortization														67.3		63.5	[3]	59.2	[3]
Noncontrolling interests’ net income (loss)														0.0		0.0	[3]	0.0	[3]
Total assets		2,743.1						2,506.0	[3]					2,743.1		2,506.0	[3]	2,352.1	[3]
Short-term borrowings		112.5						71.7	[3]					112.5		71.7	[3]	86.3	[3]
Capital expenditures														262.5		197.7	[3]	164.2	[3]
Investments in equity investees		0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Goodwill		182.1						182.1	[3]					182.1		182.1	[3]	182.1	[3]
Operating Segments | Energy Services
Segment Reporting Information
Revenues														813.8		1,105.5	[3]	1,388.6	[3]
Cost of sales														583.7		840.2	[3]	1,110.2	[3]
Operating income (loss)														141.8		169.6	[3]	178.7	[3]
Loss from equity investees														0.0		0.0	[3]	0.0	[3]
Loss on extinguishments of debt														0.0
Interest expense														(2.1)		(2.1)	[3]	(2.9)	[3]
Income (loss) before income taxes														139.7		167.5	[3]	175.8	[3]
Net income (loss) attributable to UGI														83.5		97.9	[3]	104.1	[3]
Depreciation and amortization														17.1		15.5	[3]	13.5	[3]
Noncontrolling interests’ net income (loss)														0.0		0.0	[3]	0.0	[3]
Total assets		765.6						687.6	[3]					765.6		687.6	[3]	601.5	[3]
Short-term borrowings		25.5						49.5	[3]					25.5		49.5	[3]	7.5	[3]
Capital expenditures														136.8		71.3	[3]	69.2	[3]
Investments in equity investees		17.4						6.4	[3]					17.4		6.4	[3]	0.0	[3]
Goodwill		11.6						11.6	[3]					11.6		11.6	[3]	12.6	[3]
Operating Segments | Electric Generation
Segment Reporting Information
Revenues														62.8		75.9	[3]	85.1	[3]
Cost of sales														28.5		32.2	[3]	39.6	[3]
Operating income (loss)														4.9		13.0	[3]	18.1	[3]
Loss from equity investees														0.0		0.0	[3]	0.0	[3]
Loss on extinguishments of debt														0.0
Interest expense														0.0		0.0	[3]	0.0	[3]
Income (loss) before income taxes														4.9		13.0	[3]	18.1	[3]
Net income (loss) attributable to UGI														3.6		9.6	[3]	12.6	[3]
Depreciation and amortization														13.5		12.5	[3]	10.7	[3]
Noncontrolling interests’ net income (loss)														0.0		0.0	[3]	0.0	[3]
Total assets		272.6						282.0	[3]					272.6		282.0	[3]	277.7	[3]
Short-term borrowings		0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Capital expenditures														3.6		16.7	[3]	15.6	[3]
Investments in equity investees		0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Goodwill		0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Operating Segments | UGI France
Segment Reporting Information
Revenues														1,344.7		1,122.2	[3]	1,295.5	[3]
Cost of sales														597.6		628.0	[3]	848.1	[3]
Operating income (loss)														166.1		75.9	[3]	79.1	[3]
Loss from equity investees														(0.2)		(1.2)	[3]	(0.1)	[3]
Loss on extinguishments of debt														0.0
Interest expense														(20.8)		(31.6)	[3],[6]	(25.1)	[3]
Income (loss) before income taxes														145.1		43.1	[3]	53.9	[3]
Net income (loss) attributable to UGI														84.2		27.5	[3]	20.6	[3]
Depreciation and amortization														90.5		63.7	[3]	54.5	[3]
Noncontrolling interests’ net income (loss)														(0.1)		0.0	[3]	(0.4)	[3]
Total assets		2,338.8						2,331.8	[3]					2,338.8		2,331.8	[3]	1,656.8	[3]
Short-term borrowings		0.4						0.1	[3]					0.4		0.1	[3]	0.0	[3]
Capital expenditures														75.8		65.0	[3]	50.2	[3]
Investments in equity investees		4.6						6.0	[3]					4.6		6.0	[3]	0.0	[3]
Goodwill		723.2						721.4	[3]					723.2		721.4	[3]	601.2	[3]
Operating Segments | Flaga & Other
Segment Reporting Information
Revenues														524.1		686.3	[3]	1,026.9	[3]
Cost of sales														306.2		492.0	[3]	809.9	[3]
Operating income (loss)														40.5		36.9	[3]	38.4	[3]
Loss from equity investees														0.0		0.0	[3]	0.0	[3]
Loss on extinguishments of debt														0.0
Interest expense														(3.6)		(3.6)	[3]	(4.9)	[3]
Income (loss) before income taxes														36.9		33.3	[3]	33.5	[3]
Net income (loss) attributable to UGI														27.4		25.2	[3]	27.7	[3]
Depreciation and amortization														21.9		23.2	[3]	27.1	[3]
Noncontrolling interests’ net income (loss)														0.1		(0.1)	[3]	0.0	[3]
Total assets		526.3						529.1	[3]					526.3		529.1	[3]	643.6	[3]
Short-term borrowings		0.1						0.5	[3]					0.1		0.5	[3]	8.0	[3]
Capital expenditures														24.1		22.5	[3]	23.0	[3]
Investments in equity investees		3.9						3.8	[3]					3.9		3.8	[3]	0.6	[3]
Goodwill		93.8						82.3	[3]					93.8		82.3	[3]	92.4	[3]
Corporate & Other
Segment Reporting Information
Revenues	[7]													3.9		5.7	[3]	2.7	[3]
Cost of sales	[7]													(91.6)		120.9	[3]	15.6	[3]
Operating income (loss)	[7]													77.3		(128.9)	[3]	(27.3)	[3]
Loss from equity investees														0.0	[7]	0.0	[3],[7]	0.0	[3]
Loss on extinguishments of debt														0.0
Interest expense	[7]													(0.7)		(0.7)	[3]	(0.7)	[3]
Income (loss) before income taxes	[7]													76.6		(129.6)	[3]	(28.0)	[3]
Net income (loss) attributable to UGI	[7]													25.3		(60.7)	[3]	(14.9)	[3]
Depreciation and amortization	[7]													0.8		0.8	[3]	0.7	[3]
Noncontrolling interests’ net income (loss)	[7]													48.2		(34.8)	[3]	0.0	[3]
Total assets	[7]	265.6						139.7	[3]					265.6		139.7	[3]	266.0	[3]
Short-term borrowings	[7]	0.0						0.0	[3]					0.0		0.0	[3]	0.0	[3]
Capital expenditures	[7]													0.1		0.2	[3]	0.3	[3]
Investments in equity investees		0.0	[7]					0.0	[3],[7]					0.0	[7]	0.0	[3],[7]	0.0	[3]
Goodwill	[7]	$ 0.0						$ 0.0	[3]					$ 0.0		$ 0.0	[3]	$ 0.0	[3]

[1] Includes loss on extinguishments of debt at AmeriGas Partners which decreased net income attributable to UGI Corporation by $6.1 or $0.03 per diluted share for the quarter ended June 30, 2016 and increased net loss attributable to UGI Corporation by $1.8 or $0.01 per diluted share for the quarter ended September 30, 2016 (see Note 5).

[2] Includes costs associated with an extinguishment of debt at Antargaz which decreased net income attributable to UGI Corporation by $4.6 or $0.03 per diluted share (see Note 5)

[3] Restated to reflect (1) the current-year changes in the presentation of our UGI Utilities and Energy Services reportable segments and (2) the adoption of new accounting guidance related to debt issuance costs (see Note 2 and Note 3).

[4] Represents the elimination of intersegment transactions principally among Midstream & Marketing, UGI Utilities and AmeriGas Propane.

[5] The following table provides a reconciliation of Partnership Adjusted EBITDA to AmeriGas Propane income before income taxes: 2016 2015 2014Partnership Adjusted EBITDA $543.0 $619.2 $664.8Depreciation and amortization (190.0) (194.9) (197.2)Interest expense (164.1) (162.8) (165.6)Loss on extinguishments of debt (48.9) — —Noncontrolling interests (i) 3.3 3.3 4.4Income before income taxes $143.3 $264.8 $306.4(i)Principally represents the General Partner’s 1.01% interest in AmeriGas OLP.

[6] UGI France interest expense includes pre-tax costs of $10.3 associated with an extinguishment of debt (see Note 5).

[7] Corporate & Other results principally comprise (1) revenues and expenses of UGI’s captive general liability insurance company and UGI’s corporate headquarters facility and (2) UGI Corporation’s unallocated corporate and general expenses and interest income. In addition, Corporate & Other results also include the effects of net pre-tax gains and (losses) on commodity derivative instruments not associated with current-period transactions (including such amounts attributable to noncontrolling interests) totaling $91.6, $(119.1) and $(18.0) in Fiscal 2016, Fiscal 2015 and Fiscal 2014, respectively. Corporate & Other assets principally comprise cash and cash equivalents of UGI and its captive insurance company; UGI corporate headquarters’ assets; and our investment in a private equity partnership. Through March 2014, Corporate & Other also had an intercompany loan. The intercompany loan interest is removed in the segment presentation.